Diaphragm vacuum pump

Abstract

A diaphragm vacuum pump has an electrically operated drive unit and a vacuum diaphragm, which separates a pump chamber into a drive-side part and a drive-remote part and which can be deflected by means of a movable part of the drive unit. The drive unit is an electromagnetic drive unit and the vacuum diaphragm is deflected in the direction of a linear movement generated electromagnetically in the drive unit. Preferably, a ventilation valve is also actuated the movable part. The vacuum pump is relatively small and compact and operates quietly. The vacuum pump is suitable in particular for “hands-free” applications of breastpumps.

The invention claimed is: 
     
       1. A diaphragm vacuum pump with an electrically operated drive unit and a vacuum diaphragm, the vacuum diaphragm separating a pump chamber into a drive-side part and a drive-remote part, wherein the vacuum diaphragm can be deflected by a movable part of the drive unit, wherein the drive unit is an electromagnetic drive unit, wherein the movement of the movable part is a linear movement and wherein the vacuum diaphragm is deflected in the direction of the linear movement which is generated electromagnetically in the drive unit, wherein the movable part is operatively connected to a ventilation valve for ventilating the diaphragm vacuum pump, wherein the ventilation valve has a ventilation diaphragm, wherein the vacuum diaphragm is fixedly connected to a first end of the movable part and the ventilation diaphragm is fixedly connected to a second end of the movable part, and wherein the vacuum diaphragm and the ventilation diaphragm form a mounting of the movable part within the drive unit, wherein the linear movement generated in the drive unit actuates the ventilation valve and wherein the movable part is movable by a controller in a first and a second stroke in order to generate a vacuum in the pump chamber, and is movable in a third stroke in order to actuate the ventilation valve, and wherein the third stroke is in the same direction of the second stroke and is larger than the second stroke. 
     
     
       2. The diaphragm vacuum pump as claimed in  claim 1 , wherein the first end of the movable part is opposite to the second end of the movable part. 
     
     
       3. The diaphragm vacuum pump as claimed in  claim 1 , wherein the drive unit has at least one permanent magnet and a coil former with a coil, wherein the coil is arranged on the coil former, wherein the coil former and the coil are held in a linearly displaceable manner in two directions along a longitudinal axis with respect to the magnet, and wherein the coil former forms the movable part and is fixedly connected to the vacuum diaphragm and deflects the vacuum diaphragm during the displacement of the coil former in both directions of the displacement of the coil former. 
     
     
       4. The diaphragm vacuum pump as claimed in  claim 3 , wherein the movable part comprises a piston formed by the coil former, the piston comprising a first and a second end, and wherein the vacuum diaphragm is arranged at the first end of the piston. 
     
     
       5. The diaphragm vacuum pump as claimed in  claim 4 , wherein the vacuum diaphragm has a diameter that is larger than the piston. 
     
     
       6. The diaphragm vacuum pump as claimed in  claim 5 , wherein the vacuum diaphragm is fastened centrally on the first end of the piston. 
     
     
       7. The diaphragm vacuum pump as claimed in  claim 4 , wherein the second end of the piston is held in a linearly displaceable manner. 
     
     
       8. The diaphragm vacuum pump as claimed in  claim 4 , wherein the ventilation diaphragm is fastened to the second end of the piston. 
     
     
       9. The diaphragm vacuum pump as claimed in  claim 4 , wherein the coil is a flat coil and wherein there is at least one permanent magnet, which is held in a fixed position in a housing of the diaphragm vacuum pump. 
     
     
       10. The diaphragm vacuum pump as claimed in  claim 4 , wherein the second end of the piston is mounted displaceably between an iron core and a magnet.